UK’s Lowest Carbon Road Maintenance Projects

In Autumn 2023, three local roads in the Northeast became the lowest carbon highways ever to be resurfaced in the UK, thanks to a project that has set a new benchmark for the way roads are maintained.

Working in partnership with Hartlepool Borough Council and Stockton-on-Tees Borough Council, together with international partners including Shell, Volvo CE, Wirtgen, and JCB, Tarmac reduced the carbon emissions of the road schemes by up to 80 per cent compared to projects using traditional methods. It is understood these projects have the lowest CO₂ emissions for road resurfacing in the UK without using carbon offsetting.

The project team combined an extensive range of low carbon materials, delivery techniques, and plant equipment for the very first time to resurface a section of the A689 in Wynyard, near Hartlepool, and two residential roads in Stockton-on-Tees Borough.

Warm mix asphalt was used together with a new bio-component binder from Shell which uses biogenic materials to create a technical carbon sink in the road to prevent carbon being released into the atmosphere.

The surface course and lower layer of the pavements used 30 per cent recycled asphalt planings (RAP) in the lower layer and 20 per cent in the surface course to reduce the need for primary materials. Tarmac’s asphalt manufacturing plant at Coxhoe was powered by a combination of biofuel and electricity.

A number of electric plant vehicles and prototypes were supplied by partners such as Volvo and Wirtgen, including electric and hybrid road rollers and an electric bond coat sprayer. Other plant vehicles were powered by hydrotreated vegetable oil (HVO), provided by Certas Energy, as an alternative to diesel. Materials were also kept in stores provided by ZappShelter, to minimise the energy needed to dry them out before producing asphalt, and Greener Power Solutions provided a battery unit.

Commenting on the delivery of the project, Brian Kent, national technical director – aggregates & asphalt at Tarmac, said: “While this project has delivered local environmental benefits in the Northeast, it’s also nationally significant because it provides a blueprint for how to decarbonise every element of highways delivery.

“To replicate this approach on every project will require further investment and scaling up of technology across the industry. It’s now important that we take learnings from this ground-breaking project to help inform further decarbonisation across the local and strategic road networks.”

Ana Alvernhe, general manager, Shell Construction & Road, said: “We’re delighted to contribute towards the construction of the UK’s lowest carbon road using our biogenic bitumen. Shell bitumen CarbonSink ensures that the carbon captured in the biogenic material remains locked in the bitumen and asphalt, turning the road into a technical carbon sink. This scheme is an excellent example of the supply chain working together towards the journey to net zero.”

Councillor Mike Young, Leader of Hartlepool Borough Council, said: “The Tees Valley is an area renowned for innovation, and I’m delighted and proud that we are leading the way nationally – in partnership with Tarmac – with these low-carbon road resurfacing schemes.

“Schemes such as this reflect the Council’s determination to reduce its carbon footprint to help tackle the causes of climate change. We are committed to becoming a Net Zero emissions authority by working in partnership with a range of stakeholders. To help us achieve this, we are currently developing a strategy and action plan. This is building on work we are already delivering in a number of key areas such as home energy efficiency and renewables.”

Councillor Clare Gamble, Stockton-on-Tees Borough Council’s Cabinet Member for Environment and Transport said: “We’re so pleased to be the first area in the country to have the lowest carbon emission roads as schemes like this are a big part of our commitment to achieve a Net Zero future. The Council is always looking for ways to reduce our carbon footprint and do all we can to help fight climate change, including things like building more environmentally sustainable road networks.”